<!DOCTYPE html>
<html lang="cn">
<head>
   <meta charset="UTF-8">
<meta name="viewport" content="width=device-width,initial-scale=1,minimum-scale=1,maximum-scale=1,user-scalable=no,viewport-fit=cover">
<title>封装DOM</title>
</head>
<body>
    示例
    <div id="test">test
       <div class="red">sss1</div>
        <div class="red">sss2</div>
        <div class="red">sss3</div>
        <div class="red">sss4</div>
        <div class="red">sss5</div>
    </div>
<script src="js/dom.js"></script>
<script src="js/main.js"></script>
</body>
</html>